The patch titled
Subject: userfaultfd: remove unnecessary WARN_ON() in __mcopy_atomic_hugetlb()
has been added to the -mm tree. Its filename is
userfaultfd-remove-unnecessary-warn_on-in-__mcopy_atomic_hugetlb.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/userfaultfd-remove-unnecessary-warn_on-in-__mcopy_atomic_hugetlb.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/userfaultfd-remove-unnecessary-warn_on-in-__mcopy_atomic_hugetlb.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Subject: userfaultfd: remove unnecessary WARN_ON() in __mcopy_atomic_hugetlb()
These warning here is to make sure address(dst_addr) and length(len -
copied) are huge page size aligned.
While this is ensured by:
dst_start and len is huge page size aligned
dst_addr equals to dst_start and increase huge page size each time
copied increase huge page size each time
This means these warnings will never be triggered.
Link: http://lkml.kernel.org/r/20190927070032.2129-2-richardw.yang@xxxxxxxxxxxxxxx
Signed-off-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/userfaultfd.c | 5 -----
1 file changed, 5 deletions(-)
--- a/mm/userfaultfd.c~userfaultfd-remove-unnecessary-warn_on-in-__mcopy_atomic_hugetlb
+++ a/mm/userfaultfd.c
@@ -243,10 +243,6 @@ retry:
vm_shared = dst_vma->vm_flags & VM_SHARED;
}
- if (WARN_ON(dst_addr & (vma_hpagesize - 1) ||
- (len - copied) & (vma_hpagesize - 1)))
- goto out_unlock;
-
/*
* If not shared, ensure the dst_vma has a anon_vma.
*/
@@ -262,7 +258,6 @@ retry:
pte_t dst_pteval;
BUG_ON(dst_addr >= dst_start + len);
- VM_BUG_ON(dst_addr & (vma_hpagesize - 1));
/*
* Serialize via hugetlb_fault_mutex
_
Patches currently in -mm which might be from richardw.yang@xxxxxxxxxxxxxxx are
userfaultfd-use-vma_pagesize-for-all-huge-page-size-calculation.patch
userfaultfd-remove-unnecessary-warn_on-in-__mcopy_atomic_hugetlb.patch
userfaultfd-wrap-the-common-dst_vma-check-into-an-inlined-function.patch
